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Finding the Fourth Proportional to 485.39, 726.87 and 279.45

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Solution

The fourth proportional to 485.39, 726.87 and 279.45 is: 418.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.39 : 726.87 = 279.45 : x
  2. Step 2: Convert to fraction form
    485.39/726.87 = 279.45/x
  3. Step 3: Cross multiply
    485.39x = 726.87 × 279.45
  4. Step 4: Simplify right side
    485.39x = 203,124.87
  5. Step 5: Solve for x
    x = 203,124.87/485.39
  6. Step 6: Final answer
    x = 418.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.